U.S. Pat. No. 5,049,062 (GELLERT) discloses a multi-cavity injection molding system or apparatus having a spring and sealing housing mounted between each nozzle and the manifold. Each nozzle reciprocates between a retracted open position and a forward closed position in which the tapered forward end is seated in a gate. The nozzle has a central sleeve portion with a bore that projects rearwardly into a matching bore in the housing. Disc springs received in a channel in the housing that extends around the sleeve portion of the nozzle biases the nozzle to the closed position. During each cycle, injection pressure drives each nozzle to the retracted open position, and then the spring bias drives it to the forward closed position when the injection pressure is released. The spring and sealing housing avoids leakage and misalignment as the nozzle reciprocates.
U.S. Pat. No. 7,329,118 (PRUDEN, et al.) discloses an expansion nozzle for conducting melt from a floating manifold to a mold assembly. A bushing has a bushing flange and spigot has a passage therethrough joining a nozzle inlet and an outlet. A head has a seating surface and a bore through the head slidably receiving the spigot so that the spigot is movable relative to the head over a range from abutting contact of opposing surfaces of the head and bushing flange to a limit of axial separation of the opposing surfaces. Axial separation of opposing surfaces of the head and bushing flange are maintained throughout an operating temperature range. Springs maintain sealing contact of a seating surface of the head with a mating surface of the mold assembly. Advantageously, a locating ring provides a reaction surface for the springs and supports the head to resist moments arising from axial misalignment of the expansion nozzle and mold assembly.